ASUS announced the GTX670-DC2-4GD5, a new GeForce GTX 670 graphics card based on the DirectCU II 2-slot design. The card is armed with 4 GB of GDDR5 memory, across a 256-bit wide memory interface, clocked at 6.00 GHz (192 GB/s). The card implements a custom-design PCB, with 6+2 phase Digi+ VRM that uses SuperAlloy chokes (which don't whine on load). The Digi+ VRM controller provides a certain degree of software voltage control using the GPU Tweak tool. The GPU is clocked at 915 MHz, with 980 MHz GPU Boost frequency. The card draws power from two 6-pin PCIe power connectors. Display outputs include two DVI, and one each of HDMI and DisplayPort. The new 4 GB GeForce GTX 670 DirectCU II from ASUS is expected to be priced around US $450.

i have high curiousity all around the vendor who have released nvidia's kepler cards, why the hell they did not release of its 4gb version on early release?? except evga and (maybe) kfa. it's look like they pissed me off..

i have high curiousity all around the vendor who have released nvidia's kepler cards, why the hell they did not release its 4gb version on early release?? except evga and (maybe) kfa. it's look like they pissed me off..

cmiiw

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It's probably NVIDIA's decision to let release 4GB versions of GTX 680 sooner. That's because 670 almost matches 680. So why not make an extra 100$ for every 680 sold to hardware noobs?

i have high curiousity all around the vendor who have released nvidia's kepler cards, why the hell they did not release of its 4gb version on early release?? except evga and (maybe) kfa. it's look like they pissed me off..

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Maybe you should be more mad about your inability to use the net. If you really were looking for a 4GB card they haven't been all that hard to find... Point of View , Palit (JetStream 4GB)- and it's Gainward division Phantom 4GB, along with Inno3D's were all released within a few weeks of the reference card.

EDIT: If it's solely about GTX 670's then you can substitute Galaxy's GC (the same card as the KFA2 afaiw).

I'd also assume that at the high end of the market, that vendors realise that a 4GB GTX 670 impinges on GTX 680 territory price wise. Most vendors probably also realise that potential buyers would note that 4GB is a niche product. I doubt there would be a high percentage of buyers that would opt for a 4GB 670 over a 2GB 680, especially with vendor OC'ed/cooled of the latter being in the same price range.

Bypassing that wall of numbers immediately above. The simplest explanation is that the GDDR5 used in the GTX 670/680 are 2Gbit memory IC's. The PCB/memory controller design allows for eight memory circuits (interconnects from memory I/O to individual memory pads/chips.
So;8 x 2Gbit IC's = 16Gbit (2 GB), and 8 x 32-bit I/O (each I/O circuit being 2 x16-bit data input/output)= 256-bit memory bus ( which run as four 64-bit memory controllers - one per Kepler GPC)
The simplest method of increasing memory capacity is to add memory IC's to the reverse side of the PCB mirroring the placement that already exists (i.e. the IC's sit above/below eachother with the PCB sandwiched between) and to run the memory I/O in what is called "clamshell mode", where each original combined 32-bit data input/output per memory IC is split into two 16-bit, with each of these 16-bit data I/O servicing the IC's.
So;16 x 2Gbit IC's (4GB), and 16 x 16-bit data I/O = 256-bit memory bus

Just FYI, the card is listed on newegg now, for $460 + $6.50 shipping. That is only $40 more over the 2GB version, I'd pay that, but I keep cards for a long long time these days(which is obvious from the fact that I still run GTX470s...).

Also, while 4GB fits better with a 256-bit bus, it is possible to do 3GB. The memory controllers on these cards are actually broken into 32-bit controllers. With a 2GB card, each 32-bit controller has 1 2Gbit memory chip. However, if you wanted 3GB, you could put 2 2GBit memory chips on 4 of the 8 memory controllers. This is how they do the GTX660 with 2GB on a 192-bit bus. I don't believe 3GB is an approved configuration though.